CHANDIGARH, Sept 29: Punjab Chief Minister Parkash Singh Badal has ordered registrations of a case and further investigations into ``gross irregularities'' committed in the construction of roads by the Punjab Mandi Board in Sunam sub-divisions of Sangrur district.The decision has been taken following prima facie establishing the ``correctness of allegations'' to a great extent in the preliminary inquiry conducted by the Vigilance Committee of PWD (B and R) Department on the complaint of Gurbachan Singh, the president of Sangrur Shiromani Akali Dal.Committee had inspected some of the roads referred in the complaint. The preliminary inquiry report had revealed that the quantity of stone metal retrieved was so less that it appeared only one layer of stone metal had been laid instead of two.The guilty officials have already been placed under suspension on the basis of interim report.